Endodontic materials.

Endodontic sealing materials for permanent obturation of root canals are highly variable both in chemistry of setting and in their additives. Conventional materials are based on zinc oxide-eugenol, rosinchloroform, or synthetic resins. These have been extensively tested for biological and technical properties. Most materials are slightly or moderately cytotoxic, and some — notably paraformaldehyde-containing materials — have been associated with clinical complications such as paresthesia of the mental and/or inferior alveolar nerve. Recently, Ca(OH)2-containing materials have been introduced with claims of improved clinical and biological performance. However, there is little documentation of the alleged benefits of new materials. The virtual absence of comparative clinical studies on endodontic filling materials appears to be the major obstacle to critical assessment of old materials or to adequate documentation of new formulae. A recently introduced scoring system for the radiographic assessment of apical periodontitis may aid in the future testing of endodontic materials. Results with this scoring system on extensive clinical material indicate that it is possible to discriminate among endodontic materials with small differences in clinical performance.